Mention MixinBooter o n VintageFix front page

[AechtRob]

Can you state clearly and in big type on the front, description page of the VintageFix mod that is needs MixinBooter to work? Many people don't know to go long in the Relations tab to find this stuff out.

[embeddedt]

I've added a note at the top of the description, but I do expect most people to be using a proper modded launcher, which will usually pull it for them automatically.